[Multiple symmetrical lipomatosis. Metabolic effects of excision of lipomatous tissue]. / Lipomatosi multipla simmetrica. Effetti metabolici dell'exeresi di tessuto lipomatoso.

Multiple Symmetric Lipomatosis (MSL) is a syndrome characterized by the occurrence of symmetric lipomas over various regions of the body. No clear etiology has been recognized while a frequent association with systemic metabolic abnormalities has been described. The metabolic situation of a subject affected by MSL was assessed before and after surgical excision of lipomas. A condition of impaired glucose tolerance (IGT) was verified both before and after surgery by the performance of oral glucose tolerance test, glucagon test, and daily glucose profile. No significant differences were observed after the ablation of lipomatous masses with regard to glucose, IRI, IRCP and NEFA behaviour. We concluded that the resection of lipomas can not modify glucose tolerance in MSL and that lipomas can be considered as tissues metabolically independent from the rest of body fat.

Blood lactate behavior after glucose load in diabetes mellitus.

The aim of this study was to evaluate the relationships between blood lactate and plasma glucose, insulin (IRI) and C-peptide (IRCP) during the first hour of an oral glucose load (OGTT, 100 g). Twelve controls, sixteen non-insulin-dependent (NIDDM) and four insulin-dependent (IDDM) diabetic subjects were studied. A significant increase in blood lactate was observed at 15 min in normal subjects, whereas there was a delayed increase at 45 min in NIDDM subjects, in the presence of IRCP increments of 0.31 nmol/l. In order to have a minimum significant lactate increment, the threshold value of peripheral IRCP increment was about 0.30 nmol/l. In IDDM subjects, despite considerable hyperglycemia, blood lactate concentration remained unchanged throughout the test. In normal and NIDDM subjects there was a significant negative correlation between delta lactate and delta glucose (r = -0.89, p less than 0.001) and a significant positive correlation between delta lactate and delta IRCP (r = 0.78, p less than 0.001). In conclusion, hyperglycemia itself and the lack of increase in insulin secretion do not affect blood lactate increase during OGTT; blood concentration of this metabolite depends mainly on an early insulin secretion apt to enhance tissue glucose uptake and to inhibit gluconeogenesis.